MX2008004042A - Method and apparatus for sharing slot allocation schedule information amongst nodes of a wireless mesh network - Google Patents

Abstract

A method and apparatus for communicating slot allocations of nodes in a wireless mesh network that has data exchanges between the nodes occurring during slots. Each node maintains internal tracking of its slot allocation. A node may request a slot allocation of another node, and each node is enabled to report its slot allocation to other nodes. An information element (IE) and management type messages are introduced for tracking and reporting slot allocations among mesh network nodes.

Description

METHOD AND APPARATUS FOR CONVERTING PROGRAMMING INFORMATION OF ALLOCATION OF INTERVALO BETWEEN NODES OF A NETWORK OF MESH WIRELESS FIELD OF THE INVENTION The present invention relates to a wireless mesh network, (e.g., a wireless local area network (LAN) mesh), which includes a plurality of nodes. More particularly, the present invention relates to the allocation of allocation programming information between the nodes of a mesh network.

BACKGROUND In an IEEE 802.11 mesh network (for example, in a WLAN mesh), two or more nodes exchange data during periods called intervals. The term "interval" implies multidimensional information, which may include, but is not limited to, timing information, (for example, start time and duration) in radio frequency (RF) formation, (for example, the radio and the number of channels used by the node for data exchanger), quality of service (QoS) information, ( for example, the QoS required by the data to be exchanged during the interval), personal node information (for example, the node identifiers for each node involved in the transmission of data during the particular interval), direction of the data exchange, (for example, unidirectional, bidirectional) or similar. In WLANs other than conventional mesh, optional "programming" based on 802. lie HCCA is a one-sided procedure controlled by an AP in a basic service appliance (BSS). In a WLAN mesh, the programming must be coordinated between the multiplicity of points of the mesh (MP) provided by the WLAN mesh services. Perumal K. et al. describes the use of lists of intervals in an article entitled "Neighbor Bases TDMSA Slot Assignment for WSN". Cain J.B. et al. describes the use of ad hoc networks in an article entitled "A Link Scheduling and Ad Hoc Networking Approach Using Directional Antennas". In International Application No. WO / 03003610, the characteristics of an IEEE 802.11 probe frame or response frame used in an ad hoc network are described. It would be desirable to incorporate a mechanism in the nodes of a mesh network that allows the nodes to report information with respect to their internal interval allocation program and request that programming information from other nodes. To achieve this new level of coordination, a method and apparatus for exchanging programming information between mesh points in a WLAN mesh is necessary.

THE INVENTION In an IEEE 802.11 mesh network where traffic between the nodes is scheduled at allocated intervals, efficient interval allocation is achieved through multiple nodes allowing the nodes to share their own interval allocation schedule information with each other. This provides each node with advance knowledge of the range availability of other nodes and therefore allows the nodes to allocate interval resources in an efficient and non-conflicting manner. The present invention provides a mechanism which allows the nodes in a mesh network to report their internal slot allocation program to other nodes in the network, and provides a mechanism which allows the nodes in the mesh network to request the program of internal interval assignment to the other nodes.

BRIEF DESCRIPTION OF THE DRAWINGS A more detailed understanding of the invention can be obtained from the following description, given by way of example and to be understood in conjunction with the accompanying figures 1 to 3 where: Figure 1 shows an information element format for to the interval assignment; Figure 2 shows an improved information element format according to the present invention; Y Figure 3 shows an exemplary mesh network including two nodes which are configured in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES When reference is made here later, a node includes but is not limited to a wireless transmission / reception unit (WTRU), a user equipment (UE), a mobile station, a fixed or mobile base station, a fixed or mobile access point (AP) , a fixed or mobile subscriber unit, a pager as any other type of device capable of operating in a wireless environment. Within a mesh network, each node internally keeps track of the intervals that have been assigned to it after a prior or mutual agreement with one or more personal nodes. During the particular interval, the node sends and receives data to / from those personal nodes. The record of the internal follow-up is' hereinafter referred to as a "list of assigned intervals" and comprises a list of intervals. Each node includes an internal memory which stores a list of those assigned intervals. A new information element (IE) 100 is required to represent the list of assigned ranges. Figure 1 shows the preferred format for an IE 100 according to the present invention. The IE 100 includes an element ID field of an octet 105, a length field of an octet 110, and a specific information field of the variable length element 115. In accordance with the present invention, the ID field 105 indicates that IE 100 represents an IE of the "list of assigned intervals". The length field 110 specifies the number of octets in the information field 115. Figure 2 shows the node IE 100 in greater detail, with respect to the information field 115. The information field 115 of the IE 100 list of intervals assigned includes a subfield of the size of the list 205, a plurality of subfields of information for each interval 210 ?, 2102, ..., 210N, and a subfield of size of the list of interval number 215. Each information subfield of interval 210 comprises a timing information field 220, a radio frequency information field RF 225, a quality of service (QoS) information field 230, an information field of personal nodes 235, and an address field 240 As shown in Figure 2, the subfields shown in greater detail are with respect to the # 1 interval. Therefore, the timing information field of the interval 1 220 indicates an initial time and duration of the data exchange for the interval # 1. The RF information field 225 indicates the radio channel and the number of channels used by the node to avoid changing data. The QoS information field 230 indicates the QoS required by the data to be exchanged during interval # 1. The personal node information field 235 indicates the node identifiers for each node involved in the transmission of data during interval # 1. The address field 240 indicates whether the data exchange is unidirectional, (i.e., from a transmitter to a receiver), or bidirectional (ie, to / of all the nodes involved) during interval # 1. Each node is activated to request and report its list of assigned intervals. This is preferably done by adding two types of additional management messages: 1) a "list of assigned interval request messages", and 2) a "list of assigned interval response messages". The list of assigned interval response messages preferably includes the list of assigned intervals within this body.

The present invention introduces a modification to the existing "action" management framework or frame. A category value of "interval report" is added to the definition of the action framework in a media access control entity (MAC) resident in each node of the mesh. The frames of action of the interval report are transmitted by a node to carry its interval allocation information to the other nodes. "Category" of interval report is used in the framework of the administration action to identify this new category of messages. Within this category, the two messages mentioned above "list request" and "list response" are defined. Within the "list response" message, a new IE is defined from the "list of assigned intervals". Figure 3 shows an exemplary mesh network 300 including two mesh nodes 305 and 310 which are configured in accordance with the present invention. The node 305 includes a transmitter 315, a receiver 320, a processor 325, a memory 330 and an antenna 332. The node 310 includes a transmitter 335, a receiver 340, a processor 345, a memory 350 and an antenna 352. The processor 325 at node 305 is configured to generate a list of assigned interval request messages 360, which are transmitted to transmitter 315 via antenna 332 of node 305. When node 305 wishes to transmit data to node 310, it must know when the node 310 is free to receive data. In this way, the node 305 requests the node 310 to provide its "allocated ranges", (for example, the intervals when the node 310 is busy). In this way, the node 305 can request the "list of allocated intervals" of the node 310 in order to be able to allocate some free interval for exchanging data with the node 310. Each memory 330 and 350 keeps track of the information of the interval allocation program associated with its respective node 305, 310. The memories 330 and 350 also keep track of the interval assignment information of other nodes in addition to the node residing in the respective memory. In this way, each node can keep track of the interval assignment of another node after sending a "list of assigned interval requests" and receive a "assigned interval response list". When the receiver 340 in the node 310 receives the list of assigned interval request messages 360, the processor 325 retrieves the IE 100 from the memory 350 and generates a list of assigned interval response message 365 which includes IE 100, which is transmitted by the transmitter 335 via the antenna 352 to the node 310. Each of the processors 325 and 345 includes a MAC entity (not shown) which facilitates the generation of the list of assigned interval request messages 360 and the list of assigned interval response messages 365. The present invention can be implemented in a data link layer, network layer, software and programming systems or programs, physical computing or hardware components, middleware, a future system architecture , radio resource management, or radio resource controller (RRC). The present invention is applicable to, but is not limited to, IEEE 802.11, IEEE 802. lis, IEEE 802.15, IEEE 802.15.5, IEEE 802.16 and other relevant mesh technologies.

MODALITIES 1. A wireless mesh network including a plurality of nodes which transfer the data during intervals, method for reporting interval allocation information, comprising: each of the nodes stores interval assignment information associated with the node; a first of the nodes generates and transmits a list of assigned interval request messages; and a second of the nodes generates and transmits a list of response messages of assigned intervals in response to the reception of the request message, the list of assigned interval response messages includes an information element (IE) representing the assignments of interval of the first node. 2. The method of mode 1, where the IE comprises: an element identification field (ID); a specific information field of the variable length element that contains the list of interval assignments; and a length field which specifies a number of octets in the information field. 3. The method of mode 2, where the ID field of the element and the length field are each one octet in length. 4. The method as in any of modes 2 and 3, where the information field comprises: a field of the size of the list; and a plurality of interval information fields 5. The method of mode 4, wherein each interval information field comprises: a timing information field indicating a start time and duration of data exchanged during a respective interval. 6. The method as in any of embodiments 4 and 5, wherein each interval information field comprises: a radio frequency (RF) information field indicating the radio channel and the number of channels used by the second node to exchange data during a respective interval. 7. The method as in any of embodiments 4-6, wherein each interval information field comprises: a quality of service (QoS) information field indicating the QoS required by the data to be exchanged during a respective interval. 8. The method as in any of embodiments 4-7, wherein each interval information field comprises: an information field of personal nodes indicating node identifiers for each node involved in the transmission of data during a respective interval. 9. The method as in any of the embodiments 4-8, wherein each interval information field comprises: an address field indicating whether the data exchanges by the second node are unidirectional from one transmitter to a receiver, or bidirectional to of all the nodes involved during a respective interval. 10. The method as in any of the modalities 1-9, which also includes: including an interval report in a framework of action used by an entity to control access to the environment (MAC) located on the first node, the interval report carrying the interval assignment program information associated with the first node to at least the second node of the wireless mesh network. 11. The method as in any of the modes 1-9, wherein the wireless mesh network is a wireless local area network (WLAN). 12. A wireless mesh network comprising: a first node; and a plurality of another node, where the first node and the other nodes transfer data during intervals and store allocation of interval information, the first node generates and transmits a list of assigned interval request messages, and at least one of the others nodes generates and transmits a list of response messages of assigned intervals in response to receipt of the request message, the list of assigned interval response messages includes an information element (IE) representing the allocation of the interval of the first node. 13. The wireless mesh network of mode 12, where the IE comprises: an element identification field (ID); a specific information field of the variable length element that contains the list of interval assignments; and a length field which specifies a number of octets in the information field. 14. The wireless mesh network of mode 13, where the element ID field and the length field are each one octet in length. 15. The wireless mesh network as in any of modes 13 and 14, where the information field comprises: a field of size of the list; and a plurality of interval information fields. 16. The wireless mesh network as in any of modes 13-15, wherein interval information field comprises: a timing information field indicating a start time and duration of data exchanged during a respective interval. 17. The wireless mesh network as in any of modes 13-16, wherein each interval information field comprises: a radio frequency information field (RF) indicating the radio channel and the number of channels used by the second node to exchange data during a respective interval. 18. The wireless mesh network as in any of modes 13-17, wherein each interval information field comprises: a quality of service (QoS) information field indicating the QoS required by the data to be exchanged during a respective interval. 19. The wireless mesh network as in any of the modes 13-18, wherein each interval information field comprises: a personal node information field indicating the node identifiers for each node involved in the transmission of data during a respective interval. 20. The wireless mesh network as in any of modes 13-19, wherein each interval information field comprises: an address field indicating whether the data exchanges by the second node are unidirectional from a transmitter to a receiver, or bidirectional to and from all the nodes involved during a respective interval. 21. The wireless mesh network as in any of the modes 13-20, where an interval report is included in an action frame used by a medium access control entity (MAC) located in the first node, carrying the interval report the interval allocation program information associated with the first node to at least the second node of the wireless mesh network. 22. The wireless mesh network as in any of the modes 13-22, where the wireless mesh network is a wireless local area network (WLAN). 23. In a wireless mesh network including a plurality of nodes which transfer data during intervals, a mesh node comprising: a memory configured to allocate interval allocation information associated with the mesh node; a processor electrically coupled to the memory, the processor being configured to generate a list of assigned interval request messages based on the stored interval assignment information; and a transmitter electrically coupled to the processor, the transmitter configured to transmit the list of request messages of ranges allocated to another mesh node in the wireless mesh network. 24. In a wireless mesh network including a plurality of nodes which transfer data during intervals, a first mesh node comprising: a receiver configured to receive a list of assigned interval request messages from a second node of the mesh in the wireless mesh network; a memory configured to store an information element (IE); a processor electrically coupled to the receiver and the memory, the processor being configured to retrieve the IE from the memory and generate a list of assigned interval response messages which includes the IE in response to the reception by the receiver of the message list of request of assigned intervals; a transmitter electrically coupled to the processor, the transmitter configured to transmit the list of message response messages assigned to the second node of the mesh. 25. The first node of the mode 24 mesh where the IE comprises: an element identification (ID) field; a specific information field of the variable length element that contains the list of interval assignments; and a length field which specifies a number of octets in the information field. 26. The first node of the mode 25 mesh, where the ID field of the element and the length field are each one octet in length. 27. The first node of the mode 25 mesh, where the information field comprises: a field of size of the list; and a plurality of interval information fields. 28. The first node of the mode 27 mesh, wherein each interval information field comprises: a timing information field indicating a start time and duration of data exchanged during a respective interval. 29. The first node of the mesh as in any of the modes 27 and 28, wherein each interval information field comprises: a radio frequency (RF) information field indicating the radio channel and the number of channels used by the second node of the mesh to exchange data during a respective interval. 30. The first node of the mesh as in any of the modes 27-29, where each interval information field comprises: a quality of service (QoS) information field that indicates the QoS required by the data to be exchanged during a respective interval. 31. The first node of the mesh as in any of the modes 27-30, where each interval information field comprises: an information field of personal nodes indicating the node identifiers for each node involved in the transmission of data during a respective interval. 32. The first node of the mesh as in any of the modes 27-31, where each interval information field comprises: an address field indicating whether the exchanges of data by the second node of the mesh are unidirectional of a transmitter to a receiver, or bidirectional to and from all the nodes involved during a respective interval. 33. The first node of the mesh as in any of the modes 24-32, where the wireless mesh network is a wireless local area network (WLAN).

Although the features and elements of the present invention were described in preferred embodiments in particular combinations, each feature or element can be used alone (without the other features and elements of the preferred embodiments) or in various combinations with or without other features or elements of the invention. the present invention.

Claims (11)

1. CLAIMS 1. For a wireless mesh network that includes a plurality of nodes which transfer data during intervals, a method for reporting interval allocation information, comprising: each of the nodes stores interval allocation information associated with the node; a first of the nodes generates and transmits a list of assigned interval request messages; and a second of the nodes generates and transmits a list of response messages of assigned intervals in response to the reception of the request message, including the list of response messages of intervals assigned to an information element IE, which represents the assignments of interval of the second node, characterized in that the IE comprises: a specific information field of the variable length element that includes a plurality of interval information fields, each interval information field including 1) a timing information field indicating a start time and duration of a data exchange during a respective interval, 2) a radio frequency information field, RF, which includes the radio channel and the number of channels used by the second node to exchange data during an interval respective, 3) a quality of service information field, QoS, which indicates the QoS required by the data to be exchanged during a respective interval, 4) an information field of personal nodes indicating the node identifiers for each node involved in the transmission of data during a respective interval, and 5) an address field indicating whether the data exchange is unidirectional or bidirectional. The method according to claim 1, wherein the IE further comprises: an ID element identification field; and a length field which specifies a number of objects in the information field. The method according to claim 2, wherein the element ID field and the length field are each one aspect long. The method according to claim 1, wherein the information field further comprises: a field of size of the list. The method according to claim 1, further comprising: including a range report in a frame of action used by a medium access control entity, MAC, located in the first node, carrying the interval report, program information interval assignment associated with the first node to at least the second node of the wireless mesh network. The method of claim 1, wherein the wireless mesh network is a wireless local area network, WLAN. 7. For a wireless mesh network including a plurality of nodes which transfer data during intervals, a first mesh node comprising: a receiver configured to receive a list of assigned interval request messages from a second node of the mesh in the wireless mesh network; a memory configured to store an information element, IE; a processor electrically coupled to the receiver and the memory, the processor being configured to retrieve the IE from the memory and generate a list of assigned interval response messages that includes the IE in response to the receiver receiving the list of interval request messages assigned; and a transmitter electrically coupled to the processor, the transmitter configured to transmit the list of interval response messages assigned to the second node of the mesh, characterized in that the IE comprises: a specific information field of the variable length element including a plurality of interval information fields, including each interval information field 1) a timing information field indicating a start time and duration of a data exchange during a respective interval, 2) a radio frequency information field , RF, which includes the radio channel and the number of channels used by the second node to exchange data during a respective interval, 3) a quality of service information field, QoS, which indicates the QoS required by the data to be exchanged during a respective interval, 4) an information field of personal nodes indicating the node identifiers for each node involved in the transmission of data during a respective interval; and 5) an address field indicating whether the data exchange is unidirectional or bidirectional. 8. First mesh node according to the claim 7, where the IE further comprises: an element identification field, ID; and a length field which specifies a number of octets in the information field. 9. First mesh node according to the claim 8, where the element ID field and the length field are each one octet in length. 10. The first mesh node according to claim 7, wherein the information field further comprises: a field of the size of the list. 11. The first mesh node according to claim 7, wherein the wireless mesh network is a wireless local area network, WLAN.